Android: Many launchers support different themes, but you have to download them from the Market as if they were apps, which can be incredibly cumbersome. N3xGen organizes them into their own little "theme store", making it easy to pick, download, and apply a theme in no time.

N3xGen doesn't add any new themes, it just takes ones that are available in the Market and organizes them—you can search by developer, free, paid, and even categories like "Blue", "Dark", "Gingerbread", or "Icon Pack". Right now, it supports ADW Launcher, LauncherPro, Go Launcher, CyanogenMod, and the T-Mobile Theme Changer.